Class LimitedMoveStance

Stance that attacks any unit in stance range and follows it with limited move space
This is inherited by Aggressive and Hold Ground stances
In adition to StanceComponent it has the following attributes:
stance_radius - int with the radius in which instance shold look for target
move_range - int with the radius in which instance shold move when attacking it
It also keeps track of the return position in which the unit should return when stopped attacking